HELEN, the daughter of Zeus and Leda, and the wife of Menelaus, king of Sparta; the most beautiful of women, who was carried off to Troy by Paris, to revenge whose abduction the princes of Greece, who had pledged themselves to protect her, made war on Troy, a war which lasted ten years.

HELENA, ST., the mother of Constantine the Great; is said to have visited Jerusalem and discovered the Holy Sepulchre and the cross on which Christ was crucified; d. 328, at the age of 80.  Festival, Aug. 18.  There are several other saints of the same name.

HELENSBURGH (8), a pleasantly situated watering-place in Dumbarton, on the Firth of Clyde, at the entrance of the Gareloch, 4 m.  N. of Greenock.

HELENUS, a son of Priam and Hecuba, celebrated for his prophetic foresight; is said to have deserted his countrymen and joined the Greeks.

HELIAND, an old Saxon poem of the 9th century, of great philological value, but of no great literary merit; deals with the life and work of Christ; of the two extant MSS. one is in the British Museum.

HELICON, a mountain in Boeotia, Greece, sacred to Apollo and the Muses; famous for the fountains on its slopes dedicated to the latter.

HELIGOLAND (2, but rising to 14 in summer), an islet of the North Sea, 35 m. from the mouths of the Elbe and the Weser; German since 1890; consists of the Oberland, a plateau, with some 400 houses, and the Unterland on the shore, 206 ft. beneath, with a group of 70 dwellings.  In the summer it is crowded with visitors, bathing being the chief attraction; fishing is the staple industry of the native Frisians.

HELIODORUS, the most noted and earliest of the Greek romancists, born at Emesa, Syria; flourished in the second half of the 3rd century A.D.; his romance “AEthiopica” is a love tale of great beauty and told with naive simplicity; has had considerable influence over subsequent romance writers, e. g.  Tasso.

HELIOGA`BALUS, a Roman emperor; invested, while yet a youth, with the Imperial purple by the army in 218; ruled with a show of moderation at first, but soon gave way to every manner of excess; was after four years put to death by the Praetorian Guard, and his body thrown into the Tiber.

HELIOGRAPHY, a method of signalling from distant points by means of the sun’s rays flashed from mirrors; messages can in this manner be transmitted a distance of 190 m.; it has been found of great practical value in military operations.

HELIOPOLIS (i. e.  City of the Sun), in Egyptian On, one of the oldest and most sacred cities of Egypt; was situated about 10 m.  N. of Cairo, on the eastmost branch of the Nile; it was the centre of Egyptian learning; Solon and Plato are said to have studied there, and Potiphar was one of its chief priests; the famous obelisk PHARAOH’S NEEDLE stands near; and CLEOPATRA’S NEEDLE, now on the Thames Embankment, was originally of this city.  Also the name of Baalbec.